Validation of 1-year predictive score of long-term response to interferon-β in everyday clinical practice multiple sclerosis patients

Background and purpose The Rio score (RS) and the modified Rio score (MRS) are two scoring systems that can identify the early predictive factors of disability progression in relapsing−remitting multiple sclerosis (RRMS) patients treated with interferon-β (IFN-β). The objective of the study was to validate the usefulness of the RS and MRS in a large cohort of multiple sclerosis patients treated with IFN-β in daily clinical practice. Methods The analysis included a cohort of RRMS patients treated with different formulations of IFN-β for at least 1 year. The RS and MRS were used to classify the patients after 1 year of treatment. Multivariate analysis was performed to identify predictive variables of suboptimal response at 5 years, defined as Expanded Disability Status Scale confirmed progression or switching to a second-line therapy. Results Sixty-nine of 416 included patients were considered as suboptimal responders at 5-year evaluation. The possible score range was 0–3. A higher risk of suboptimal response was found for RS and MRS in the presence of ≥2 scores (hazard ratio 3.0, P = 0.002, and hazard ratio 5.0, P < 0.0001, respectively). Conclusions Our study confirmed, in a daily clinical setting, that MRS had a better specificity and accuracy than RS in identifying the patients who will have a poor response to long-term IFN-β treatment.